Understanding and controlling the electronic structure of thin layers of quantum materials is a crucial first step towards designing heterostructures where new phases and phenomena, including the metal-insulator transition (MIT), emerge. Here, we demonstrate control of the MIT via tuning electronic bandwidth and local site environment through selection of the number of atomic layers deposited. We take CaVO₃, a correlated metal in its bulk form that has only a single electron in its V⁴⁺ 3d manifold, as a representative example. We find that thick films and ultrathin films (≤ 6 unit cells, u.c.) are metallic and insulating, respectively, while a 10 u.c. CaVO₃ film exhibits a clear thermal MIT. Our combined X-ray absorption spectroscopy and resonant inelastic X-ray scattering (RIXS) study reveals ...

A viable hydrogen economy has thus far been hampered by the lack of convenient hydrogen storage solutions for long hauls and transportation/delivery infrastructure. Current approaches require high pressure and/or complex heat management systems to achieve acceptable storage densities. Development of hydrogen storage solutions operating at near ambient conditions can mitigate the complexity, cost and safety perception issues currently hindering the hydrogen economy. We have assembled a team of experts in both experimental and computational modelling approaches to synthesise and characterise a porous manganese hydride material, which projects to offer roughly four times the volumetric hydrogen storage capacity of 700 bar incumbents ...

Transition metal dichalcogenides (TMDs) are interesting for understanding the fundamental physics of two-dimensional (2D) materials as well as for applications to many emerging technologies, including spin electronics. Here, we report the discovery of long-range magnetic order below T_M = 40 and 100 K in bulk semiconducting TMDs 2H-MoTe₂ and 2H-MoSe₂, respectively, by means of muon spin rotation (μSR), scanning tunneling microscopy (STM), and density functional theory (DFT) calculations. The μSR measurements show the presence of large and homogeneous internal magnetic fields at low temperatures in both compounds indicative of long-range magnetic order ...

The high brilliance of new X-ray sources such as X-ray Free Electron Laser opens the way to non-linear spectroscopies. These techniques can probe ultrafast matter dynamics that would otherwise be inaccessible. One of these techniques, Transient Grating, involves the creation of a transient excitation grating by crossing X-ray beams on the sample. Scientists at PSI have realized a demonstration of such crossing by using an innovative approach well suited for the hard X-ray regime. The results of their work at the Swiss Free Electron Laser have recently been published in the journal Optics Letters.

On April 8, 2019 DORA-PSI the new repository for publications of PSI staff and users of our facilities will go live. The new system is hosted and maintained by the joint library Lib4RI of of Eawag, Empa, PSI and WSL, and will replace the publication tool of the DUO system that served as the PSI publication database for the last 13 years. All publications registered in DUO are currently being migrated to the new system.
From March 29 on, the import of further publications into DUO will be disabled. Afterwards - from April 8 onwards - you may import your publications into DORA-PSI directly. Of course and as before, DUO will further serve for all other purposes related to the administration of user operation at PSI.
DORA will provide features like green open access and also options for full text search. It will harvest publication metadata from Scopus, Web of Science and the RCSB protein data bank. Also in the new system it will be of utmost importance that you link your publications to the beamlines of PSI where the respective data have been taken.
Should you have any questions about DORA-PSI, do not hesitate to contact Lib4RI per email directly.

A new automatic sample exchange system named TELL (high-Throughput Enabling Large capacity sample Loader) has been developed by the MX group for the SLS MX beamlines and the SwissMX fixed target station at the SwissFEL. The TELL system offers enhanced storage capacity, improved reliability and faster sample exchange compared to the existing CATS system, thereby enabling high throughput crystallography at the SLS and the SwissFEL. It successfully entered user operation at the SLS beamline X06SA (PXI) on 01 February 2019. The TELL system is of high importance for the SLS MX beamlines users from academia and industry.

The members of the League of advanced European Neutron Sources (LENS) held their first General Assembly and the first Executive Board meeting on 26 March 2019 in Liblice, the Czech Republic. The consortium adopted and signed Statutes detailing the purpose of LENS, guiding the work of the statutory bodies, and laying the framework for Working Groups responsible for the execution of foreseen activities. The Director of Institut Laue-Langevin (ILL) in France, Helmut Schober, was elected as LENS Chair, and the Director of the ISIS Neutron and Muon Source in the United Kingdom, Robert McGreevy, as Vice-Chair. For the Swiss spallation neutron source SINQ the head of the PSI NUM division Christian Rüegg signed the documents. More information

The recent submission deadline for SμS proposals passed by the end of February. Finally, a total of 178 proposals has been submitted asking for 911 days of beamtime. These are remarkably large numbers taking into account that one of the instruments (LTF) has been taken out of user operation. The largest number of proposals was submitted for GPS (52), followed by DOLLY (44), LEM (37), GPD (27) and HAL-9500 (18). The large number of proposals results in significant overbooking factors for several instruments.
The proposal review committee will gather at PSI on April 11-12. Soon afterwards we aim to inform the users about the results of the beamtime allocation for 2019. The next submission deadline will be in December 2019 for the 2020 beam time period. The exact date will be announced in due time.

An International Symposium on Structure Biology for Drug Discovery will be held June 25th to 27th at the PSI (main auditorium). Topics center around structure-based methods in drug discovery and include opportunities at XFELs, methods development and the complementary interplay of single particle cryo Electron Microscopy and XFEL analysis. The symposium boasts an impressive list of keynote speakers from industry and academia. There are still available slots for short presentations; please submit your abstract ASAP if you are interested. Seats are limited, so please register in time here.

The annual User Meeting of the Particle Physics at PSI’s ring cyclotron took place January 28-30, 2019. The ring cyclotron went into operation in 1974: 45 years a world-leading facility! In some of the years, two user meetings were held. The 2019 edition was the 50th BVR (‘Benutzer-Versammlung Ring’). A large number of participants filled the auditorium for the open session on Tuesday afternoon, following a motivating theory talk and the presentations of new proposals and ongoing smaller scale efforts, see program.
As over the past ten years, the Monday was spent on in depth reviews of some of the major experimental projects by subcommittees. The BVR committee reviewed all projects on Tuesday and Wednesday morning. The oral deliberation by the committee chair on Wednesday afternoon, as always, preceded the written reports and explained the assignments of beam time.

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PSI Facility News addresses the users of the PSI large facilities and appears quarterly in English. Any feedback is highly welcome! More information. 

Contact: PSI User Office, Phone: +41-56-310-4666, Email: useroffice@psi.ch